Windows Mail Folder Structure

I am using Windows Mail on a Vista Home Premium 32-bit computer.

I imported some folders from Outlook Express and created others. When
I look at the Local Folders folder, I see some folders with names I
created, multiple folders with the same basic name and numbers after
them, like "folder xy" and folder xy (1)." I also have a number of
"Imported Folders" with alphanumeric characters at the end of the file
names, like "Imported Fo eb."

How can I clean up the file structure so that all e-mails are in
correctly-named folders? I use Thunderbird when I travel and having a
"normal" file structure would make exporting and importing a lot easier.

Thanks!


--
DougR